In recent years, much time and effort has been expended in trying to develop means by which coal can be cleanly burned. One means of accomplishing this is by burning it in a fluidized bed to which limestone is added. The limestone reacts with the sulfur in the coal to form calcium sulfate, preventing the formation of SO.sub.x in the exhaust gases which would pollute the atmosphere. Although there is a considerable amount of liquid fuels, heavy residuals, and other lighter oils available that contain high sulfur, little effort has been made to develop a system for burning these fuels cleanly. It is difficult to burn these fuels in a fluidized bed since it is difficult to get good fuel distribution throughout the bed. Also, carbonization of the fuel injector nozzles can be a problem.